Turbo-generator installation



April '29, 1930. G. B. WARRE N 1,756,894

TURBO GENERATOR INSTALLATION Filed May 23,v 192,9

Invnbor": Glenn BAX/arren, by w His Attorn eg- Patented Apr. 29, 1930UNITED STATES PATENT oFFlcr.

GLENN B. WARREN, OF SCHENECTADY, NEW YORK, ASSIGNOR [DO-GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK TURBO-GENERATOR INSTALLATIONApplication filed May 23,

The demand by central stations and other users of power generatingapparatus is on the one hand for very large units while on the otherhand the available floor space in the stations is greatly restrictedand, in the majority of cases, cannot be enlarged for rea-- sons whichwill be appreciated. This has led to placing the turbines one above theother inspection or repair involves disassembling and removing the highpressure unit as well, a proceeding which costs a large sum of money initself and greatly increases the period of time that the apparatus as awhole out of service. This latter has a direct bearing on operatingcosts and may, and usually does, seriously handicap the station insupplying current to its customers.

In order that an idea may be had of the great weights involved in theseturbme installations, reference may be made as an example to a two unitmachine of 50,000 kilowatts output, of which I have knowledge.

In this case the high pressure unit weighs approximately 90,000 poundsand the cover of the casing, diaphra s andJipper half of the exhausthood 0 the low pressure unit weigh approximately 80,000 pounds.

I have invented an arrangement of turbines and generators which has allof the advantages of saving floor space and at the same time permits theturbines and gener- .ators to be opened separately, and this withoutinterference from the other parts of the assembly. Briefly stated, myinvention comprises dividing the turbine into two principal parts orun'its, and to attain the greatest benefits of the invention the highpressure unit is made much smaller than the low pressure unit, say ofthe order of thirty percent for the former and seventy ercent for thelatter. The low pressure tur inc and its generator are, due to theirreat weight and size, mounted on the foun ation of the station and inaxial alignment. Upon the generator are mounted the smaller highpressure turbine and its smaller generator, and so arranged 1929. SerialNo. 365,415.-

that no portion overhangs the low pressure turbine in a manner toprevent it from being opened. For this purpose the casing of thegenerator driven by the low pressure turbine is so shaped andconstructed as to afford a firm foundation for the parts supported.

thereby.

For a consideration-of what I believe to be ator unit which isillustrative of my invention, and Fig. 2 is an end view of the same.

As an illustration,but not as a limitation of my invention, I haveelected to illustrate it in connection with an installation of 50,000kilowatts capacity.

3 indicates a support which may be a steel or concrete foundation or abed plate which is supported thereby. Upon the support or foundation ismounted a low pressure turbine 4 of large capacity having an exhausthousing 5 adapted to be connected to a condenser 6 of which only theupper art is shown. The casing of the turbine is sp it in a horizontalplane as is usual and is so arranged that it can be lifted to expose thewheels and other parts ,without interference from any other part of theassembly. The front end of the turbine casing is supported by brackets7, one'on each side, which are arranged to. take care of expansionstrains due to heat. These brackets are supported by a suitablesupporting member carried by the foundation or by a separate ....pillaras desired. Exhaust fluid, such as steam, is admitted to the turbine bythe inlet 9'from the exhaust opening or open-' illustration. At the lefthand end of the tur-' bine in addition-to the shaft bearing is a speedgovernor indicated by the reference character 8*, and below it is an oiltank 8 from which oil, is supplied by a pump to the bearings,

The massive electric generator which is driven by-the low pressure unitis indicated at 13. Asthe internal construction is unimportant to'thepresent invention it has not been illustrated. It is suflicient to saythat the casing forms a unitary structure and that the rotor may beremoved by an endwise movement according to standard practice.

T he shafts of the two machines are in axial alignment and are coupledby any suitable or well-known means. On the outer end of the generatorshaft is a bearing 13*" and a smaller generator 14 which may supply our-1 rent for energizing the field winding of both generators, for drivingauxiliaries or for any other purpose.

The casing of the generator 13 may be made somewhat heavier than isnecessary for purely electrical reasons, in order to support the loadplaced on top of .it, and is finished differently on the top, beingflat.

Supported wholly by the generator casing is a high pressure turbine 14and an electric generator 15, the shaft axes of the turbine units andgenerators being in'the same vertical planes As shown, they are mountedon a bed plate 16 which in turn is fastened to the casing of the largegenerator 13. The high pressure turbine and its generator are sosupported that there is nothing-to interfere with the raising of thecasing or the exhaust housing of the low pressure turbine to expose theinternal parts. In other words,

flow of motive fluid may be reduced to a minimum. One outstandingadvantage of the arrangement is that the high pressure unit does nothave to be lifted or opened or its alignment aflected when work is being'done on the low pressure unit. As illustrated, the turbine and itsgenerator have a capacity of about thirty percent of the total, the lowpressure turbine and its generator furnishing the remainder. The shaftsof the turbine and generator are in the same axial plane and they may beconnected by any suit- I able or usual means. The shafts of both theupper and lower units are in the same Vertical plane, and as far aspossible the metal used in each construction is symmetrically disposedabout its shaft so as to reduce the distortion effects due to heating.Steam or other elastic fluid under high pressure is admitted to the highpressure unit by the conduit 17 subject to the control of a combinedemergency and throttle valve 18 of any suitable construction. Forconvenience the opcrating means for the valve is located at the portboth the high pressure unit and its generator without requiring anyadditional metal except possibly a small amount to give to the lowercasing the proper shape.

The arrangement has the advantage that it eliminates the necessity of aseparate foundation in the power house for one turbine, i. e. the high.pressure unit. Another and outstanding advantage is that the casing ofboth turbines can be'opened, one without disturbing the other, and fromoverhead. The -generators can also be opened or in spected with I alsopermits, due to their location one over the other, of the use of asingle cooling system for both generators, passing the air or othercooling medium from one directly to the other in the region of theirmeeting surfaces. For example, cool air may be supplied to the lowergenerator by the conduits 20 and 21 and after passing through bothgenerators is delivered to the conduit 22 which may be taken as a partof a cooleror as a conduitleading thereto,

Eliminating one foundation reduces the cost of the installation andsaves valuable floor space which would otherwise be required, andfurthermore the large generator 13 affordsasubstantially betterfoundatlon for the other generator and its turbine than is usuallyprovided or in many cases 1s possible to provide. d

Dividing the turbine into two units of the capacity stated makes a veryadvantageous division of the load for reheating or superheating of themotive fluid between the two units since the volume of fluid to'behandled will require only conduits of'reasonable size and cost.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. A turbinegenerator installation comprising a. low pressure turbineand a generator driven thereby, a foundation therefor, a high pressureturbine anda generator driven thereby which are supported wholly by theout disturbing the turbines. 1t

firstnamed generator .and are 'bothaxially K high pressure unit, andconduit means for supplying motive fluid to the turbine units.

2. A turbine generator installation comprising high and low pressureturbine units,

. the former being of lower capacity than the latter, generators drivenby the turbine units each of which is in axial alignment withtitsdriving unit, the high pressure unit and its generator being whollysupported by the generator of the low pressure unit with the axesthereof occupying the same vertical plane as the axis of said generator,a foundation for the low pressure unit and its generator, and conduitsfor supplying motive fluid in series 7 to the two turbine units.

*3. A turbine generator installation comprising a foundation, a lowpressure turbine, a generator driven thereby, said turbine and generatorbeing mounted on the foundation in axial alignment, a high pressureturbine unit, a generator driven therebywhich parts are also in axialalignment, said unit and its generator being wholly supported on top ofthe first named generator and being axially displaced from the lowpressure turbine unit to permit of the latter being opened to expose itsinternal parts without interference, the high pressure unit beinglocated at the end of the generator adjacent the low pressure unit so asto reduce the length of the connecting conduit, and a conduit forconveying the exhaust of the high pressure unit to the low pressureunit.

In witness whereof, I have hereto set my hand this 21st day of May,1929.

GLENN B. WARREN.

